Hot vapor treatment in dyeing cellulose triacetate



United States Patent 6 2,999,002 HOT VAPOR TREATMENT IN DYEING CELLULOSE 'I RIACETATE Jack A. Dayvault and Fred Fortess, Charlotte, N.C., as-

signors to Celanese Corporation of America, New

York, N.Y., a corporation of Delaware I No Drawing. Filed Sept. 22,1958, Ser. No. 762,285 20 Claims. (Cl. 8-94) The present invention relates to the dyeing, with aqueous suspensions of disperse dyes, of textile materials comprising polymeric polyesters such as organic acid esters of cellulose, e.g. cellulose triacetate, and linear polyesters such as polyethylene terephthalate, emphasis being placed upon the depth of shade which is achieved and the rapidity of the dyeing process. The invention is especially directed to the dyeing of cellulose triacetate textile materials, which in addition to increased depth of shade will exhibit increased dimensional stability as well as an increased safe ironing temperature.

The invention is particularly concerned with improvements in the known dyeing process in which textile materials are padded-with aqueous suspensions of disperse dyes and dried and thereafter treated with vapors of'a chlorinated aliphatic hydrocarbon, notably trichlorethylene, and then rinsedin hot water and scoured with soap. By the term disperse dye it is-intended to encompass the class of substantially water-insoluble dyes, this class having been originally introduced for the dyeing of cellulose acetate and usually applied from fine aqueous suspension. An object of the invention is the provision of a treatment procedure for dyeing polyester textile materials.

Another object of the invention is to improve the dyeing of cellulose triacetate and polyethylene terephthalate textile material in which the dry material impregnated with particles of disperse dyeis subjected to'hot solvent vapor so that therapidity of the dyeing process is enhanced and greater depth of shade achieved. 7

A further object of the invention is the treatment of cellulose triacetate textile materials impregnated with disperse dyes for the purpose of simultaneously dyeing these materials and improving the resistance of the dyed material to heat as evidenced by improved strength, less change in shade, less stiffening and improved resistance to glazing upon subjection of the material to scorching or irom'ng conditions.

Other objects and advantages will be apparent from the following description and claims.

In accordance with one aspect of the invention, the textile material to be treated is padded with an aqueous suspension of' disperse dye and dried. Thereafter, the dried textile material impregnated with the disperse dye is subjected to the vapors of a halogenated benzene, e.g. chlorinated, brominated, etc., a dialkyl ketone having at least 4 carbon atoms, or an alkyl ether of an alkylene glycol. The temperature of the vapor generally ranges from about 140 to 300 F. and preferably from about 175 to 275 F. The vapor pressure of the vapor may be less than 760 mm. Hg at the temperature employed, in which case subatmospheric pressures may be employed. Superatmospheric pressure can also be employed where the volatility of the material is adequate.

Preferably the textile material is passed through a chamber containing the vapors in equilibrium with the corresponding boiling liquid.

The textile material is permitted to remain in the chamher for a period of time sufficient to effect infusion or migration of the dye into the textile materials. A feature of the present invention resides in the fact that the residence time in the vapor chamber can be significantly reduced in comparison with the residence time required when chlorinated aliphatic hydrocarbons are employed as the source of the vapor. For example, textile materials which generally require a dwell time of 5-6 minuteswhen using trichlorethylene can be dyed to a greater depth of shade within 60 seconds in accordance with the present invention. in some instances, a dwell time of as little as 5 seconds has been found to be suitable. I

Since the vapor dyeing process to which thepresent invention relates is primarily of significance in connection with the continuous dyeing of textile materials, reduction in the dwell time in the vapor is of obvious commercial advantage. The importance of being able to achieve a full depth of shade from a given dye is also advantageous.

The preferred chlorinated benzene which is used in accordance with the invention is monochlorbenzene. Corresponding homologues of monochlorbenzene can also be used with good result, particularly the mono-chlorinated alkyl derivatives, notably monochlortoluene and mono chlorethylbenzene. Dialkyl derivatives may also be employed, e.g. monochlorxylene. Polychlorinated aromatic compounds may also be employed, such as orthodichlorbenzene. If desired, the alkyl substituent in the benzene nucleus may be halogenated so long as a chlorine substituent is present in the aromatic nucleus. 7

Representative dialkyl ketones having at least 4 carbon atoms include the di-lower alkyl ketones such as methyl ethyl ketone, di-ethyl ketone, halogenated derivatives such as chloromethyl-ethyl-ketone, and the like. Representative alkyl ethers of alkylene glycols include lower alkyl ethers of lower alkylene glycols such as the mono-ethyl of ethylene glycol, di-ethyl ether of ethylene glycol, monoethyl of propylene glycol-1,3, ethyl ether of ethylene glycol mono-acetate, and the like.

In general, the preferred vapors are those of monochlorbenzene, methyl ethyl ketone and the mono-ethyl ether of ethylene glycol, both because of the good results and because they boil Within the preferred temperature range at atmospheric pressure. In addition to its rapid action and increased depth of shade methyl ethyl ketone, for example, gives dyed cellulose triacetate fabrics which, following subsequent heat treatment, are stronger than cellulose triacetate fabrics dyed in conventional manner and then heat treated. Whereas heat treatment of cellulose triacetate fabrics may decrease the fabric strength by about 15%, the heat treatment step on fabrics which have been subjected to vapors of methyl ethyl ketone, mono-ethyl ether of ethylene glycol or monochlorbenzene does not significantly reduce the strength of the fabric and in many instances increases the strength. Actually the novel vapor treatments raise the safe ironing temperature of cellulose triacetate textile materials in that the materials are more resistant to shade change, stiffening or glazing or ironing. (lonsequently heat treatment can be eliminated if' desired while still realizing the advantages accruing therefrom.

In accordance with another aspect of the invention, the' use of the halogenated benzene vapor, e.g. monochlorbenzene, is especially advantageous since in addition to the general superiority of the vapors in accordance with the present invention it allows dye fixation on linear polyester textile material, such as polyethylene terephthalate, to a much greater extent than other vapors such as those of chlorinated aliphatic hydrocarbons. In addition, con ventional, i.e. secondary or ripened, organic acid esters of cellulose can also be dyed efiectively through use of monochlorbenzene.

After the solvent vapor treatment is completed, the textile material is rinsed and scoured in conventional man ner to remove surface dye and any solvent which has condensed on the material. Rinsing is preferably performed with water heated to a temperature of -95 C., the rinsing treatment being desirably performed for a period of about 60 seconds or more. Securing is de- Patented Sept. 5, 1 961,

sirably efiected in a water solution of soap having a temperature of about 60 C. and containing 1 gram of soap flakes per liter of solution. T o insure the complete removal of surface dye and solvent, the scouring treatment is desirably performed for a period of about minutes. The scoured dyed textile materials are exceedingly washfast and produce substantially no staining when washed with uncolored fabrics at 140 F.

Textile materials which may be dyed in accordance with the present invention include finished articles or piece goods, yarns, staple fiber, etc. The term cellulose triesters as employed herein has reference to cellulose esters containing fewer than 0.29, and preferably fewer than 0.2, free hydroxyl groups per anhydroglucose unit of the cellulose molecule. Conventional or secondary cellulose esters of organic acids generally have in the neighborhood of 0.6 free hydroxyl groups per anhydroglucose unit. The preferred esters are acetates but esters of other lower alkanoic acids, or mixtures of lower alkanoic acids, can also be employed.

The invention is illustrated in the examples which follow, wherein Cl. refers to the latest edition of the Colour Index:

EXAMPLE I The following specific disperse dye solution is employed as representative of disperse dyes which may be used in the padding step of the vapor dyeing process, the formula which follows indicating the number of grams of each component which is used per liter of water solu- I tion Component: Grams per liter Eastman Blue GLF Cl. Dispersed Blue 27. Eastone Red N-GLF. 20 CI. Dispersed Red 35. Interchem Yellow HDLF- 20 CI. Dispersed Yellow 37. Nafka crystal gum Triton X-lOO (oxyethyl- 25.

ated nonyl phenol)"- l.

Table I [Shade to scale of 1-10 increasing in depth] Cellulose Triacetate Polyethylene Terophthalato 1 Light Grey. 7 Medium Brown.

5 Medium Brown" Trlchlorethylene 10 Dark Brier-mm- Mouochlorben zene Other chlorinated aliphatic hydrocarbon vapors produce substantially the same results as trichlorethylene. In no instance was a full depth of shade achieved using a chlorinated aliphatic hydrocarbon within the second treatment time. Substantially the same results are obtained by repeating the process on fabric of conventional secondary cellulose acetate in place of cellulose triacetate.

EXAMPLE 11 By the process of Example I a cellulose triacetate woven fabric was padded and then subjected for 60 seconds to vapors of (1) methyl ethyl ketone and (2) mono-ethyl ether of ethylene glycol in equilibrium with the corresponding boiling liquid. After scouring, as compared With a depth of shade of 5 for trichlorethylene the depth of shade with methyl ethyl ketone was 8, and 10 with mono-ethyl ether of ethylene glycol.

aesaooe 4 EXAMPLEIII Samples of cellulose triacetate fabric padded and dyed as in Example I were heat treated by being subjected to radiant heat for 20 seconds with a fabric temperature of 425 F. and the strength of the fabric was compared before and after heating. Other samples were placed for 10 seconds between two metal plates heated to 410 F.

to determine the extent of shade change, stiffening and.

glazing (scorch test). The results for samples which (Sl=slight; Lt=light; Mod=moderate.)

In brief, when vapors in accordance with the invention are employed dyeing is more rapid and more effective and the product is better adapted to resist heat. This improved heat resistance is manifested by a significant improvement in tensile strength retention upon heat treatment as well as by a significant improvement in resistance to glazing, stiffening and shade change.

The invention is applicable throughout the range of disperse dyes and a representative list of disperse dyes with which the invention may be employed is set forth in Table III which follows:

Table III Dispersol F. Yellow A 300 Dispersed Yellow 1.

Dispersol Printing Yellow 63---- Dispersed Yellow 3. Dispersol Fast Red R 300.

Duranol Red X3B 300 Dispersed Red 11. Duranol Printing Blue G200--- Dispersed Blue 26. Duranol Printing Blue Green BS" Dispersed Blue 7. Seriosol Yellow N New Dispersed Yellow. Serisol Fast Yellow GD New Dispersed Yellow 3. Serisol Fast Yellow PL Dispersed Yellow 9. Serisol Fast Orange YL Dispersed Orange 11. Serisol Fast Scarlet GD Dispersed Red 19. Serisol Fast Scarlet BD Dispersed Red 1. Serisol Fast Crimson BD Dispersed Red 13. Serisol Fast Pink B 300 Dispersed Red 3. Serisol Brilliant Blue G Dispersed Blue 14. Serisol Fast Blue BRL Dispersed Blue 19.

Serisol Dark Blue.

It is to be understood that the foregoing detailed description is given merely by way of illustration and that many variations may be made therein without departing from the spirit of our invention.

Having described our invention, what we desire to secure by Letters Patent is:

l. A method of dyeing a polymeric polyester textile material selected from the group consisting of cellulose triesters and linear polyesters comprising impregnating said textile material with an aqueous suspension of disperse dye, drying said impregnated material and subjecting said impregnated and dried material to a vapor selected from the group consisting of a chlorinated benzene, a dialkyl ketone having at least 4 carbon atoms and an alkyl ether of an alkylene glycol.

2. A method of dyeing a textile material as recited in claim 1 in which said vapor is an equilibrium with the corresponding boiling liquid.

3. A method of dyeing a textile material as recited in claim 2 in which said liquid has a boiling point between about 140 and 300 F.

4. A method of dyeing a textile material as recited in claim 1 in which said vapor is a chlorinated benzene.

5. A method of dyeing a textile material as recited in claim 1 in which said vapor is monochlorbenzene.

6. A method of dyeing a textile material as recited in claim 1 in which said vapor is a di-alkyl ketone having at least 4 carbon atoms. p

7. A method of dyeing a textile material as recited claim 1 in which said vapor is methyl ethyl ketone.

8. A method of dyeing a textile material as recited in claim 1 in which said vapor is an alkyl ether of an alkylene glycol.

9. A method of dyeing a textile material as recited in claim 1 in which said vapor is the mono-ethyl ether of ethylene glycol.

10. A method of dyeing a textile material as recited in claim 1 in which said textile material is passed through a chamber saturated with said vapors, said textile material remaining in said chamber for about 5 to 60 seconds.

11. A method of dyeing a polymeric polyester textile material comprising impregnating said material with an aqueous suspension of disperse dye, drying said impregnated material and passing said impregnated and dried material through a chamber containing a chlorinated benzene vapor.

12. A method of dyeing as recited in claim 11 in which said vapor is monochlorbenzene.

13. A method of dyeing as recited in claim 11 in which said polymeric polyester is polyethylene terephthalate.

14. A method of dyeing as recited in claim 11 in which said polymeric polyester is cellulose triacetate.

15. A method of dyeing as recited in claim 11 in which said polymeric polyester is secondary cellulose acetate.

16. A method of simultaneously dyeing and improving the heat resistance of cellulose triacetate textile material comprising impregnating said material with an aqueous suspension of disperse dye, drying said impregnated material, and passing said impregnated and dried material through a chamber saturated with a vapor selected from the group consisting of a chlorinated benzene, a di-alkyl ketone having at least 4 carbon atoms and an alkyl ether of an alkylene glycol thereby to dye said material and to achieve improved resistance to elevated temperature.

17. A method of dyeing as recited in claim 16 in which said textile material remains in said chamber for about 5 to seconds.

18. A method of dyeing a textile material as recited in claim 16 in which said vapor is monochlonbenzene.

19. A method of dyeing a textile material as recited in claim 16 in which said vapor is methyl ethyl ketone 20. A method of dyeing a textile material as recited in claim 16 in which said vapor is the mono-ethyl ether of ethylene glycol.

References Cited in the file of this patent Mellor et al.: J.S.D.C., 67, 620, page 623, col. 1, 1951.

Du Pont: The Technical Bulletin, vol. 8, No. 2, pp. 69-78, June 1952.

Dyeing and Finishing Dacron, Du Pont Bulletin, page 11, February 1956.

Garrett: The Journal of the Society of Dyers and Colourists, vol. 73, N0. 8, pp. 365-374, August 1957. 

1. A METHOD OF DYEING A POLYMERIC POLYESTER TEXTILE MATERIAL SELECTED FROM THE GROUP CONSISTING OF CELLULOSE TRIESTERS AND LINEAR POLYESTERS COMPRISING IMPREGNATING SAID TEXTILE MATERIAL WITH AN AQUEOUS SUSPENSION OF DISPERSE DYE, DRYING SAID IMPREGNATED MATERIAL AND SUBJECTING SAID IMPREGNATED AND DRIED MATERIAL TO VAPOR SELECTED FROM THE GROUP CONSISTING OF A CHLORINATED BENZENE, A DIALKYL KETONE HAVING AT LEAST 4 CARBON ATOMS AND AN ALKYL ETHER OF AN ALKYLENE GLYCOL. 